1. Field of the Invention
The present invention relates to a cloth hanging engaging device which easily connects a curtain rail to various types of screens such as a curtain, an interior material engaging device which is disposed between a mounting body such as indoor ceiling, floor, panel material and the like and a sheet material such as mat, carpet, wall material, ceiling material, dash board and the like to fix the mounting body and the sheet material by engagement, synthetic resin engaging device for fixing threads or the like and an engaging device which can substitute for clothes buttons.
2. Description of the Related Art
A cloth hanging engaging device has been disclosed in for example, Japanese Patent Laid-Open Publication No. 4-104909, in which, in order to improve efficiency in operation for replacing a curtain or screen, the cloth hanging engaging device is disposed between a runner to be attached to a curtain rail or guide bar and a curtain or the like so as to facilitate the attachment and detachment of the curtains or the like. This cloth hanging engaging device has a plurality of hook elements in plural rows on a surface of a plate-like substrate which are formed integrally therewith and a hook-shaped hanger portion is formed of the same synthetic resin material integrally on a top end of the substrate so as to be hooked on the aforementioned runner. The hook elements are arranged vertically and a plurality of rows thereof are disposed in the width direction from the right to the left. The hooking direction of the hook elements in the same hook row is the same. The hook elements of all the hook rows which are adjacent to each other may be directed to the same direction or part of the hook elements may be directed to opposite direction. This kind of the engaging device secures an engaging strength by directing the hooking direction thereof in most hook rows upward as shown in FIG. 5 because the curtain is supported while it hangs downward.
Various kinds of interior materials are attached to, for example, automobile ceiling, floor, door panel portion or house""s wall portion, ceiling, floor and the like. A surface fastener is used for such an attachment. Although conventionally, ultrasonic fusion, pressure-sensitive welding and the like are used to fix a male/female engaging device of the surface fastener to a mounting body or interior material, such methods have deficiency in durability and fixing strength. Therefore, interior material fixing engaging device having a post-like protrusion with two-wing elastic engaging portions composed of a pair of right and left wing pieces on its tip provided on a rear surface of the plate-like substrate so that it protrudes therefrom, and a multiplicity of the hook elements are formed of synthetic resin. Then, the elastic engaging portions are elastically deformed and inserted into a hole provided in the mounting body. Using an elastic restoration of the same engaging portion, front and rear surfaces of the mounting body are nipped and fixed by the substrate and engaging portion.
Such interior material fixing engaging devices have been disclosed in, for example, Japanese Patent Publication No. 51-651, Japanese Utility Model publication No. 54-26089, and Japanese Utility Model Laid-Open Publication No. 57-31250, indicating that this is used often for interior construction of houses as well as automobile. Recently, use of the aforementioned elastic engaging portion as a curtain rail runner has been proposed in for example, Japanese Utility Model Laid-Open Publication No. 3-21285. In such a kind of the interior material engaging device, usually, to avoid generation of directivity in engaging strength, the surface of a substrate is divided to plural sections and a plurality of hook elements are disposed in each section. The hooking direction of the hook elements arranged in the same row is set to be the same and the hooking directions are set opposite between adjacent hook rows. Then, the hooking directions are perpendicular to each other between adjacent sections.
As this kind of the engaging device, for example, string length adjusting engaging device applicable for loop tie, opening tightening device for various bags, or hem tightening device of various jumpers, or opening/closing engaging device for clothes substituting for ordinary buttons are used as well as the aforementioned engaging device. These engaging devices each have a plurality of hook elements made of synthetic resin on the substrate surface made of the same synthetic resin having any shape.
Any of the aforementioned hook elements formed on the substrate surface of each of these engaging devices has the same hooking direction in the same hook row. On the other hand, for these kinds of the engaging devices, in order to secure a sufficient engaging strength, the amount of plasticizing material to be added to synthetic resin which is composition material is set lower than an engaging device in which an ordinary elasticity is demanded. Therefore, brittleness increases although some extent of high rigidity is secured. Thus, in case where the hook element disposed at the most outer end of a hook row is directed inward of the hook row, if an external force directed outward is applied to the hook element when the hook element at the most outer end portion engages with the mating loop element or the engaging device is operated by holding with the finger so as to attach it, the engaging device may be deformed largely. At this time, there is nothing that backs up the same hook element and this hook element is located near an edge of the substrate, therefore this hook element often reaches a breaking point so that it is broken.
Particularly, in case of the aforementioned cloth hanging engaging device, most of the curtain weight is supported by the hook elements disposed at a lower end of the engaging device so that a larger load is applied as compared to the other hook elements. As a result, fatigue is increased with a passage of time if the engagement/disengagement is repeated. For example, when it is intended to separate the curtain or the like from its top end, the hook elements located at a second tier from a bottom as well as the hook elements disposed at the bottom edge are likely to be broken. This is because there are no hook elements or substrate which backs up the hook elements in a bending direction located at the first and second tiers disposed at the bottom edge when the curtain or the like is separated. Thus, they are bent more largely as compared to the hook elements disposed upward thereof so that fatigue is increased as well as the aforementioned brittleness, thereby leading to breaking. The same thing can be said for the above described various kinds of the engaging devices also.
According to, for example, Japanese Patent Laid-Open Publication No. 7-155221 (U.S. Pat. No. 5,615,461), it has been proposed that the hooking direction of all the hook elements disposed on the peripheral portion of the engaging device or at least those located at the most outer end thereof are directed outward. For example, if it is intended to separate the curtain attached to the engaging device downward from its top end, the hooking direction of all the hook elements located at the bottom end of the engaging device coincide with the separation direction, so that the separation can be achieved very smoothly. Further, no unnecessary force is applied to the hook elements disposed at the lower end thereby ensuring a long period use.
Even if the curtain load is applied to hook elements located above the bottom end of the engaging device and having upward hooking direction, the backup function is exerted because hook elements whose hooking direction is directed downward exist below the aforementioned hook elements. Consequently, they are not deformed largely and even if the engagement is repeated, the fatigue is not increased and therefore, they bear a long period use and are not broken. Further, a force is applied in various directions to the curtain portion attached to the bottom end of the same engaging device. For example, if an external force is applied, to the curtain, in such a direction to separate from the bottom end of the engaging device, a force resisting that external force is exerted because the hooking direction of the hook elements located at the bottom end is directed downward. Consequently, they are not released easily so that the curtain becomes unlikely to be released from the engaging device.
Although in the engaging device disclosed in the above Japanese Patent Laid-Open Publication No. 7-155221, a damage due to breaking of the hook element disposed at the peripheral portion of the substrate is avoided, it has been made evident that a problem peculiar to this kind of the engaging device arises when the hooking direction of the hook elements disposed at the peripheral portion of the substrate of the hook row is directed outward as described above.
That is, as described above, in this kind of the engaging device, rigidity of the material is raised to increase the engaging strength. On the other hand, a hook tip of the aforementioned hook element is larger as compared to a molded surface fastener having an excellent flexibility, which is an ordinary simple engaging device for combining different cloths. However, as for the aforementioned thread fixing engaging device, the dimension of the hook tip is 0.3 mm in its lateral width as viewed from front and a height of the entire hook from the surface of the substrate is 0.9 mm, and a height of a bottom face of the hook tip from the surface of the substrate is 0.5 mm. Further, the hook element has a curved shape whose thickness decreases gradually from a top end of a stem thereof to the hook tip which is directed toward the surface of the substrate.
Thus, the hook tip is tapered along a distance of only 0.4 mm, and therefore, a tip of each hook element has sharpness like a pin. Therefore, when this engaging device is handled for engagement or disengagement, not only pain is felt as the finger touches the hook element, but also the finger may be pierced by the hook tip and injured. In this point, this kind of the hook element lacks the safety. Further, there is a danger that the hook element may be broken and stick in the finger.
The present invention has been achieved in views of the above described problems and an object of the invention is to provide an engaging device which is capable of utilizing advantages of an engaging device made of synthetic resin, protecting the hook elements disposed at the edge of the engaging device and securing the safety when the engaging device is operated.
To achieve the above object, according to the invention, there is provided an engaging device having a plurality of hook elements disposed in plural rows on a surface of a substrate so as to engage with an engaging portion of a mating member having a plurality of loop elements on a surface thereof, wherein projections projected substantially vertically from the substrate are disposed at at least one of outermost ends of each of the hook rows disposed on the engaging device so as to be formed integrally with the engaging device.
That is, when the projection and the hook element are disposed such that the projection and the hook tip of the hook element oppose each other at the most front or most rear end of the hook row, even if the finger is moved toward a hook end of the hook element, the finger never touches the hook tip and therefore it is never injured because the projection functions as a blocking member for the hook element opposing the projection. On the other hand, in case where the projection is disposed in an end opposite to the direction of the hook element, even if a mating loop element engages with the hook element disposed in front of the projection, for example, and then the hook element is pulled backward by the same loop element so that it may be bent largely, the projection functions as a backup member so that when the bent hook element comes into contact with the projection, it is never deformed further. Consequently, the same hook element is never broken. Further, if the projections are disposed on both the ends of the hook row, the above described respective functions are exerted, so that the finger is never pierced and injured by the hook element disposed at the most front end of each hook row or the hook element disposed at the most rear end thereof is not broken.
Preferably, a height of the projection from the surface of the substrate is set higher than the position of a bottom face of a front end of the hook element. In the present invention, a lower limit height of the projection when the above-described function is secured is specified. That is, this height is a height which prevents the finger from touching the hook end of the hook element in the hook row and allows the entire hook element to be bent backward in an allowable limit. Further, this height allows the hook element to be deformed enough for the mating engaging loop element to be removed from the hook element. Because of the above described function and dimensions of the projection, the upper limit height of the projection is desired to be an upper limit height of the hook element.
The present invention specifies typical kinds of the engaging device. In the meantime, there are other engaging devices like, for example, an engaging device for attaching a grinding cloth to a grinding machine.
The mating member may be a hanging cloth such as a curtain and screen, and the engaging device has a plurality of hook rows provided on the surface of the substrate and further has a hook-like hooking portion provided at an upper end of the substrate through a neck portion. The mating member may be a plate-like interior material and the engaging device has a plurality of hook rows provided on the surface of the flat plate-like substrate having some degree of rigidity and further includes a post-like protrusion having two-wing shaped elastic engaging portion at a top end thereof provided in the center of a back face of the substrate, so that the elastic engaging portion is inserted into an engaging hole formed in a mounting body and fixed to the mounting body by engagement.
The mating member may be clothes or various kinds of bags having a pair of opposing opening/closing edge portions, and the substrate is attached to one of the opening/closing edge portions of the clothes or the various kinds of bags and has a plurality of hook rows on the surface thereof. The mating member may be the clothes or the various kinds of bags and the substrate is disposed in the vicinity of an opening of the clothes or the various kinds of bags and having a plurality of hook rows provided on the surface thereof, while the substrate has an insertion hole through which a thread is to be inserted and thread engaging/disengaging means for engaging or disengaging the thread inserted through the thread insertion hole.